Firm joins were obtained between Ti(C,N)-based cermet and steel with Ag-Cu-Zn-Ni filler metal by vacuum brazing. The effects of technological parameters such as brazing temperature, holding time, and filler thickness on the shear strength of the joints were investigated. The microstructure of welded area and the reaction products of the filler metal were examined by scanning electron microscopy (SEM), metallographic microscope (OM), energy-dispersive X-ray analysis (EDS), and X-ray diffraction (XRD). The brazing temperature of 870°C, holding time of 15 min, and filler thickness of 0.4 mm are a set of optimum technological parameters, under which the maximum shear strength of the joints, 176.5 MPa, is achieved. The results of microstructure show that the wettability of the filler metal on Ti(C,N)-based cermet and steel is well. A mutual solution layer and a diffusion layer exist between the welding base materials and the filler metal.
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